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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:expandtab:shiftwidth=2:tabstop=2:
*/
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsWinUtils.h"
#include "Compatibility.h"
#include "DocAccessible.h"
#include "nsAccessibilityService.h"
#include "nsCoreUtils.h"
#include "mozilla/a11y/DocAccessibleParent.h"
#include "mozilla/Preferences.h"
#include "mozilla/StaticPrefs_accessibility.h"
#include "nsArrayUtils.h"
#include "nsICSSDeclaration.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/Element.h"
#include "nsXULAppAPI.h"
using namespace mozilla;
using namespace mozilla::a11y;
using mozilla::dom::Element;
// Window property used by ipc related code in identifying accessible
// tab windows.
const wchar_t* kPropNameTabContent = L"AccessibleTabWindow";
/**
* WindowProc to process WM_GETOBJECT messages, used in windows emulation mode.
*/
static LRESULT CALLBACK WindowProc(HWND hWnd, UINT msg, WPARAM wParam,
LPARAM lParam);
bool nsWinUtils::sWindowEmulationStarted = false;
already_AddRefed<nsICSSDeclaration> nsWinUtils::GetComputedStyleDeclaration(
nsIContent* aContent) {
nsIContent* elm = nsCoreUtils::GetDOMElementFor(aContent);
if (!elm) return nullptr;
// Returns number of items in style declaration
nsCOMPtr<nsPIDOMWindowInner> window = elm->OwnerDoc()->GetInnerWindow();
if (!window) return nullptr;
ErrorResult dummy;
nsCOMPtr<Element> domElement(do_QueryInterface(elm));
nsCOMPtr<nsICSSDeclaration> cssDecl =
window->GetComputedStyle(*domElement, u""_ns, dummy);
dummy.SuppressException();
return cssDecl.forget();
}
bool nsWinUtils::MaybeStartWindowEmulation() {
// Register window class that'll be used for document accessibles associated
// with tabs.
if (IPCAccessibilityActive()) return false;
if (Compatibility::IsJAWS() || Compatibility::IsWE() ||
Compatibility::IsDolphin() || Compatibility::IsVisperoShared()) {
RegisterNativeWindow(kClassNameTabContent);
sWindowEmulationStarted = true;
return true;
}
return false;
}
void nsWinUtils::ShutdownWindowEmulation() {
// Unregister window call that's used for document accessibles associated
// with tabs.
if (IsWindowEmulationStarted()) {
::UnregisterClassW(kClassNameTabContent, GetModuleHandle(nullptr));
sWindowEmulationStarted = false;
}
}
void nsWinUtils::RegisterNativeWindow(LPCWSTR aWindowClass) {
WNDCLASSW wc;
wc.style = CS_GLOBALCLASS;
wc.lpfnWndProc = WindowProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = GetModuleHandle(nullptr);
wc.hIcon = nullptr;
wc.hCursor = nullptr;
wc.hbrBackground = nullptr;
wc.lpszMenuName = nullptr;
wc.lpszClassName = aWindowClass;
::RegisterClassW(&wc);
}
HWND nsWinUtils::CreateNativeWindow(LPCWSTR aWindowClass, HWND aParentWnd,
int aX, int aY, int aWidth, int aHeight,
bool aIsActive,
NativeWindowCreateProc* aOnCreateProc) {
return ::CreateWindowExW(
WS_EX_TRANSPARENT, aWindowClass, L"NetscapeDispatchWnd",
WS_CHILD | (aIsActive ? WS_VISIBLE : 0), aX, aY, aWidth, aHeight,
aParentWnd, nullptr, GetModuleHandle(nullptr), aOnCreateProc);
}
void nsWinUtils::ShowNativeWindow(HWND aWnd) { ::ShowWindow(aWnd, SW_SHOW); }
void nsWinUtils::HideNativeWindow(HWND aWnd) {
::SetWindowPos(
aWnd, nullptr, 0, 0, 0, 0,
SWP_HIDEWINDOW | SWP_NOSIZE | SWP_NOMOVE | SWP_NOZORDER | SWP_NOACTIVATE);
}
LRESULT CALLBACK WindowProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam) {
// Note, this window's message handling should not invoke any call that
// may result in a cross-process ipc call. Doing so may violate RPC
// message semantics.
switch (msg) {
case WM_CREATE: {
// Mark this window so that ipc related code can identify it.
::SetPropW(hWnd, kPropNameTabContent, reinterpret_cast<HANDLE>(1));
auto createStruct = reinterpret_cast<CREATESTRUCT*>(lParam);
auto createProc = reinterpret_cast<nsWinUtils::NativeWindowCreateProc*>(
createStruct->lpCreateParams);
if (createProc && *createProc) {
(*createProc)(hWnd);
}
return 0;
}
case WM_GETOBJECT: {
// Do explicit casting to make it working on 64bit systems (see bug 649236
// for details).
int32_t objId = static_cast<DWORD>(lParam);
if (objId == OBJID_CLIENT) {
RefPtr<IAccessible> msaaAccessible;
DocAccessible* document =
reinterpret_cast<DocAccessible*>(::GetPropW(hWnd, kPropNameDocAcc));
if (document) {
document->GetNativeInterface(getter_AddRefs(msaaAccessible));
} else {
DocAccessibleParent* docParent = static_cast<DocAccessibleParent*>(
::GetPropW(hWnd, kPropNameDocAccParent));
if (docParent) {
if (StaticPrefs::accessibility_cache_enabled_AtStartup()) {
msaaAccessible = MsaaAccessible::GetFrom(docParent);
} else {
docParent->GetCOMInterface(getter_AddRefs(msaaAccessible));
}
}
}
if (msaaAccessible) {
LRESULT result =
::LresultFromObject(IID_IAccessible, wParam,
msaaAccessible); // does an addref
return result;
}
}
return 0;
}
case WM_NCHITTEST: {
LRESULT lRet = ::DefWindowProc(hWnd, msg, wParam, lParam);
if (HTCLIENT == lRet) lRet = HTTRANSPARENT;
return lRet;
}
}
return ::DefWindowProcW(hWnd, msg, wParam, lParam);
}